My invention will be described hereinafter with reference to parking meters but it will be understood that such use is exemplary only.
At present almost all parking meters controlling the use of positions in automobile parking lots are coin-operated and mechanical in nature. In recent years there has been an increase in the cost of such parking to the point where quarter-dollars may be the only accepted coin and a spell of one or two hours of parking time may require the provision of many such coins. This presents an availabilty problem that is a growing source of inconvenience to frequent users of such meters. Attempts have been made therefore to devise credit card related systems to operate parking meters.
One approach is the use of a conventional bank credit card, or Visa or Mastercharge card, to purchase a magnetically encoded parking card entitling the purchaser to a number of units, for example 20 hours, of parking time (see for instance Kenyon UK Patent Application No. 2027965A). The parking card could be dispensed from a bank money dispensing machine or from an adjacent stand-alone dispensing machine after a standard bank credit card, or Visa or Mastercharge card, had been temporarily magnetically encoded to allow dispensing of the parking card. The parking card could then be carried in a purse or wallet and used in the parking location. Typically a card with magnetic regions recorded as on an audio cassette tape must be scanned by a reading head at a known speed and this entails problems of cost and reliability. Some applications of magnetic cards involve reading of the card's magnetic regions, and change of certain of the magnetic regions to correspond to the amount of service supplied. Then the cash value is subtracted from the purchased value of the card and the card imprinted with the unused value remaining. This requires a complicated mechanical mechanism and an associated sophisticated electrical system. An example of such a system may be found in Pfost et al., U.S. Pat. No. 4,020,325.
Because of the high cost, such systems have not come into general use in connection with parking meters. It is conceivable that such a system might be set up as a single unit to supply parking time to a large array of individual parking meters, which would distribute the cost. It could dispose coin-like parking tokens that could then be used as substitutes for coins in regular parking meters. However many street areas have parking meters in widely dispersed locations not conveniently serviced by a central token dispenser. The need, therefore, exists for a low-cost box unit that could be added to an existing parking meter post to provide parking time with the aid of a low-cost card. The electrical power requirement of each box should be low enough to be provided by battery rather than 60 Hz electrical power line.
In the present state of the art of magnetically encoded cards, it is difficult to apply them economically to parking control. My invention makes use of encoded cards of special design that are interrogated by light of suitably chosen photon energies to achieve parking control at considerably lower cost.